With industrial and technical development, electronic devices such as a computer have been rapidly spread and most organizations including companies and government offices conduct relevant business using electronic devices such as a server computer, a personal computer (including a notebook), a tablet PC, and a mobile device. Further, electronic devices have been used for control and management in various other fields such as mechanical and factorial facilities, industrial facilities, and military facilities.
As industry is reorganized to incorporate the use of electronic devices having computer functions, damage to electronic devices or leakage of important information is frequently caused by malicious codes or viruses that are intentionally spread into the electronic devices.
In consideration of this situation, various measures have been developed and are used in government and municipal offices, companies, and military facilities to prevent leakage of information and to provide protection from viruses etc. However, recently, as general-purpose USB ports that allow quick access to a computer have been widely used with development of memory devices, it frequently occurs that third parties can easily accesses a main computer and put viruses into the computer or take out important information.
That is, most computers on the market now have at least one general-purpose USB port that allows easy access to the computer, so anybody can easily access desired computers by connecting a USB memory to a USB port.
Accordingly, unauthorized users can easily connect a USB memory to a computer and put a virus into the computer or take out important information, so there is a need for measurements against this problem.
In consideration of the problem, the applicant(s) has proposed a USB lock device that can prevent connection of unauthorized memories when a USB memory is connected to a USB port.
However, many electronic devices also have a LAN port for connection via wire to provide internet or telephone communication, and a LAN connector connected to a LAN cable is supposed to the connected to the LAN port, so external electronic devices or memories can be connected to the LAN ports. Accordingly, it is strongly required to develop a device that can safely lock the LAN ports.